Charles j



(No Model.)

0. J. EAMES.

RBDUGING STACK. No. 407,000. Patented July 16, 1889.

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UNITED STATES PATENT OFFICE.

CHARLES J. EAMES, OF NEY YORK, N. Y.

REDUClNG-STACK.

SPECIFICATION forming part of Letters Patent No. 407,000, dated July 16,1889.

Application led January 19, 1889. Serial No. 296,840. (No model.)

T0 all whom it may concern:

Be it known that I, CHARLES J. EAMES, a citizen of the United States,residing at New York city, in the State of New York,have iuventedcertain new and useful Improvements in Reducing-Stacks for the Reductionof Iron and other Ores; and I hereby declare the following to be a full,clear, and exact description of the same, reference being had to theaccompanying drawings, wherein- Figure 1 is a vertical central sectionof a reducing-stack embodying my invention. Fig. 2 is an elevation ofthe reducing-stack.V Eig. 3 is a horizontal section on the line as, Fig.l, showing the gas-burner and its chamber. Fig. 4 is a detached top orplan view of the drop-grate. Fig. 5 is a detail view of a portion of theburner.

Like symbols refer to like parts wherever they occur.

My present invention relates to the construction of stacks for thedeoxidation or reduction of iron and other ores by such methods asutilize carbonio oxide or equivalent gases as the heat-conveying medium,and which bring the heated gases in direct contact with the materialoperated on.

It has for its object the production of an inexpensive stack which canbe operated with either solid or gaseous fuel, or both, if desired, canbe easily repaired, can be operated by unskilled labor, and whose outputwill equal, if not exceed, that of -more expensive plants. XVhile ofvalue for the reduction of ores generally, it is particularly adaptedfor the reduction of iron ore where the strata processes (described byme in several applications of even date herewith) are followed.

To this end the main features of the present invention may be broadlystated as follows: First, in a stack for reducing ores, said stackhaving a damper at the top, a dumpinggrate to discharge the contents ofthe stack, a closed chamberbeneath the stack provided with means forcontrolling the draft through the grate and for cutting oitl said draft,and a series of air-ports at the base of the stack for maintaining lowcombustion above the grate; sec-ond, a reducing-stack closed below by adrop-grate, beneath which is a slide for forming a burner-chamber,within which chamber is arranged a removable gas-burner or gas-supply;third, a reducing-stack provided at its base with a drop-grate the uppersurface of which is lined with fire-brick, which forms a checker-workheat-storer and, finally, there are other minor features of invention,all of which will hereinafter more fully appear.

I will now proceed to describe my invention more specifically, so thatothers skilled in the art to which it appertains may apply the same.

In the drawings, l indicates a tapering shell of plate or boiler iron orother suitable material, suitable proportions for which will be threefeet diameter at the top, five feet dialneter at the bottom, and iivefeet high, though any other desired proportions may be selected by theconstructor, provided the stack is given sufficient taper to make itdischarge freely when the grate is dropped.

In the walls of the stack l are a series of doors (5, arranged atdifferent heights and preferably in step form, as shown in Fig. 2, whichdoors serve for introducing and spreading the charge or successivelayers of the ore and carbon or reducing agents.

Encircling the base of the stack l are a series of air-ports 7, whichmay be closed by plugs of fire-brick or by doors, as shown in thedrawings. These ports serve to admit air to support low combustion. Thisshell l is lined with fire-brick 2, provided above with a suitabledamper 3 and below with a drop-grate 4. It is.supported on suitablearches 5 of brickwork to obtain a pit 16, to receive the charge aftertreatment, and the arches should be of sufficient height to allow theworkmen free access for removing the charge and resetting the grate l.

The grate 4 is preferably a two-part dropgrate hinged at the sides, asshown at 8 8, and having its upper surface lined or faced withfire-bricks 9 9, (see Fig. 4,) which form a checker-work, which willbecome and remain highly heated. It will be noted that the grate 4 is inreality only a shell or frame for holding the checker-work 9 9.

Extending across the arch or base, which supports the stack l, is aslide (or slides) 10, which,when the stack is in operation, (reduc- IOOing the ore,) is pushed in to form a chamberA v be obtainedwhendesired.However, theblast is only used in cases of emergency to preventscaffolding of the material, or sometimes to urge the fire before thematerial to be treated has been charged into the stack.

The natural draft is the one most commonly used to urge the fire in thepreliminary heating of the furnace.

During the reducing operations the airports 7 at the base of stack 1supply all the air which under ordinary circumstances is eitherrequisite or admissible.

12 indicates a removable burner which, when in use, is introduced intochamber 1l through side doors 14, (see Fig. 2,) and through which doorsit can be withdrawn previous to discharging the reduced charge into pit16. This burner 12 is preferably made up of a series of Bunsen burnersof the general character shown in Fig. 5,wherein a indicates thegas-box, b the gas-jet, and c a central airtube, the full-line arrowindicating the course of the gas and the dotted-line arrow that. of theair.

A reducing-stack having substantially the features of constructionhereinbefore pointed out can bei used for reducing ores of anycharacter, wherein the passage of heated or heatfoonveying neutral gasesthrough4 the material operated on is practiced or is admissible; and thegases can be generated either in the lower stratum or fuel-bed or can besupplied from an external source through burner l2, (or other pipe,) andeither oxidized in chamber 1l or in the checker-work 9 9.

When working with solid fuels to generate the carbonio oxide in thestack, a bed-layer A, of cokeor anyother suitablefcarbon, ofconsiderable thickness, is placed-aon grate 4 and checker-work 9 9, andby means of suitable kindling` and a blast or the natural draft broughtto incandeseence. When incandescent, a stratum or layer B of the ore tobe reduced, mingled with the reducing agent, (the whole in the form of agranular mass,) is placed on the carbonaceous layer A and leveled oifthrough the appropriate door 6. Upon the stratum B of ore to be treatedis placed a lsecond layer A of carbon, and on that a second layer B ofthe ore to be treated, mixed with the reducing agent, the successivelayers being leveled and their depth regulated through the appropriatedoors. Thus the alternate layers A B are continued until the stack isfilled to within a few inches of the top, when the treatment of thecharge can be commenced.

The carbonio oxide for treating the ore can, as before specified, begenerated by low combustion in the lower carbonaceous layer A by theadmission of air in limited quantity through ports 7 7 at the base ofthe stack; or gaseous fuel can be admitted through pipes 12, and (afterthe first or preliminary heating of the stack and bed A) low combustioninduced therein above grate 4 in checker-work 9 9 by vadmitting alimited amount of air through ports 7 7.

Having thus set forth the nature and advantages of my invention, what Iclaim, and desire to secure by Letters Patent, is-

1. A stack for reducing ores, having a damper at its top,a drop-grate atits bottom,a slide below the drop-grate, and a series of airports at itsbase just above the plane of the grate, substantially as and for thepurposes specified.

2. A stack for reducing ores, havinga dumping-grate at its base, aseries of air-ports encircling the stack at its base, aslide arrangedbelow said grate and forming a closed chamber beneath the grate, and aseries of charging-doors arranged on successive levels, substantially asand for the purposes specified.

3. A reducing-stack having at its base a drop-grate provided with afacing or checkerwork of fire-brick, substantially as and for thepurposes specified.

4. The combination, with a reducing-stack having a'drop-grate, of a,detachable or sliding gas-burner arranged below the grate,substantiallyas and for the purposes specilied.

5. The combination, with a reducing-stack having a drop-grate, of aremovable or sliding burner arranged .below the grate anda removableslide aranged below the burner, substantially as and for the purposesspecilie'd.

. ln testimony wliereof I affix my signature, in presence of twowitnesses, this 19th day of January, 1889. CHARLES J. EAMES.

Vitnesses:

E. T. WALKER, F. l. CoRNwALL.

